The adjustments made to the addon was to make TNT Power & Radius higher.  Attached is the Addon that was default and minorly adjusted.

Expected:

Minecraft to run smoothly unless TNT was lit.  It was working in 1.14

What Happened:

Extreme lag like I've never seen before

Steps to Reproduce:

1) Add Addon

2) Open World

3) Fly around

4) Notice the lag

5) Notice as you load new chunks it gets worse